Packaging means for emanating pyrethroid effective in controlling flying insects

Abstract

The invention provides a packaging means for retaining vapour active pyrethroids comprising a holder and a cellulosic based substrate or matrix impregnated and / or dosed with the vapour active pyrethroid, wherein the holder comprises a topl), a bases and a longitudinal member vertically extending from between the topw and base, and wherein the cellulosic matrix has a honeycomb configuration adapted to be retained between the top and base and has a surface area so as to achieve sufficient emanation of the vapour active pyrethroid to control flying insects. The invention also provides methods of emanating vapour active pyrethroids and the use of packaging means according to the invention for retaining and emanating vapour active pyrethroids.

Description

TECHNICAL FIELD [0001] The present invention relates generally to insect control and more particularly a packaging means for retaining and emanating vapour active pyrethroid that is effective in controlling flying insects, particularly mosquitoes. BACKGROUND ART [0002] The control of flying insects in an indoor or an outdoor area has traditionally been achieved using articles or devices that dispense insecticide vapours into the atmosphere. Such articles or devices generally burn or heat a liquid or solid substrate to vaporise the active ingredient. For instance, in controlling mosquitoes, coils impregnated with an active ingredient are burnt so that heat from combustion causes the release of the active ingredient into the atmosphere, citronella oil candles are burnt so as to heat the citronella oil and allow it to evaporate into the atmosphere, while electric devices electrically heat the active ingredient so that it vaporises and is dispersed into the atmosphere. Battery operated,...

AI Technical Summary

Benefits of technology

[0008] The present inventors have found that imparting verticality (or height) to the substrate results in a higher rate of emanation of the pyrethroid and therefore more efficient insect control.

[0012] Desirably, the holder and the cellulosic based substrate or matrix are adapted to allow the cellulosic matrix to be releasably retained in the holder and replaced as required. This may be achieved by the provision of a slot within the periphery of each of the top and base and a card on each end of the cellulosic based substrate or matrix, wherein the cards are able to be slid into the slots thereby allowing the cellulosic based substrate or matrix to be releasably attached to the holder. This configuration has the advantage of allowing the cellulosic based substrate or matrix to be replaced without the need to detach the longitudinal member from the top or base while the top and base are in the closed or open state. It is also envisaged that the cellulosic based substrate or matrix may be adapted to receive the longitudinal member through an aperture thereby retaining the cellulosic based substrate or matrix between the top and base. In this configuration, the cellulosic based substrate or matrix is able to be replaced by detaching the top or base, or both, from the longitudinal member, mounting the cellulosic based substrate or matrix about the longitudinal member, and reattaching the top or base, or both, to the longitudinal member.

[0025] The phrase “surface area” is intended to mean the geometric surface area or the two dimensional surface area of the cellulosic based substrate or matrix. For instance, in a preferred embodiment where the cellulosic based substrate or matrix is paper, the surface area is the total area of both sides of the paper. Generally, the inventors have found that an increase in the surface area, particularly the effective emanation surface area, increases the emanation rate of the vapour active pyrethroid from the cellulosic based substrate or matrix into the atmosphere. It will be understood that the effective emanation surface area is the area of the cellulosic based substrate or matrix that allows emanation of the pyrethroid into the atmosphere. For instance, the inventors have found that increasing the number of folds in a paper substrate reduces the emanation rate of the pyrethroid from the paper substrate.

[0035] In the context of the present invention, the inventors have found that paper thickness and type will affect the emanation rate. Further, they have found that increasing the level of vapour active pyrethroid will increase the duration of emanation. Also increasing the surface area, increasing the temperature and increasing the air flow will increase the emanation rate, while folding the paper will decrease the emanation rate.

[0036] The holder and the cellulosic based substrate or matrix containing the pyrethroid may be folded between an open form and a closed form such that they are expandable or are re-closable structures. This means that when insect control is not required, the holder and / or the cellulosic based substrate or matrix may be closed and stored in a form which minimises the surface area containing the vapour active pyrethroid that is exposed to the atmosphere. Conversely, when insect control is required, the holder and / or the cellulosic based substrate or matrix may be expanded into an open form thereby increasing the surface area of cellulosic based substrate or matrix containing the pyrethroid that is exposed to the atmosphere allowing the pyrethroid to emanate into the atmosphere. It is also envisaged that the- amount of vapour active pyrethroid emanated into the atmosphere may be controlled by maintaining the top and base in an intermediate state between the open and closed states so that the cellulosic based substrate or matrix is in a partially expanded form.

Problems solved by technology

The combustion of mosquito coils requires a safe burning site and results in ash and smoke.

The burning of a candle exposes a naked flame and therefore requires a safe burning site, while the use of electricity to heat an insecticidal device is costly in some developing countries and is not portable.

The above known ambient temperature products, however, also have disadvantages.

Firstly, many of the prior art products are only effective in small, enclosed spaces and require significant air movement for the insecticide to be effective in a larger area of space.

Secondly, there is a short falling in the number of cost-effective products that are able to work efficiently using low doses of insecticide for the control of insects other than moths, such as mosquitoes.

There are, however, a number of disadvantages associated with such arrangements: In for instance the flat substrate arrangements, due to their flat configuration, the available surface area from which active ingredient is able to be emanated is small.

In the case of the bridge or fan configuration, the honeycomb-like cells on the extreme ends of the fan are not fully expanded thereby leading to an inefficient use of available (or potential) surface area from which active ingredients are able to emanate.

Clearly, from a consumer point of view, having to attach a hook to a ceiling or a wall in order to allow the lantern to be hung is both time consuming and laborious and therefore undesirable.

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